Introduction

The sexual double standard (SDS) is the different valuation that people make of sexual behaviour depending on whether it is men or women who carry out said sexual behaviour. The patriarchal model has traditionally allowed men greater sexual permissiveness than women. The latter have been looked upon more negatively when behaving similarly with regard to sexual initiation, premarital behaviour or promiscuity (Soller & Haynie, 2017; Zaikman et al., 2016). The various social movements in favour of women have thus far failed to bring about equality in sexual roles even though behaviours such as sexual relations outside of the couple or premarital sex are currently more widely accepted and, generally speaking, there is greater freedom vis-à-vis sexual activities (Bordini & Sperb, 2013; Moya et al., 2006). Over the last few decades, research has been carried out from a threefold perspective: (1) the prevalence of double sexual standard has been examined; (2) the various factors which are related to the SDS and influence on it have been investigated and, finally, (3) work has been carried out to create and validate instruments designed to evaluate this construct. The prevalence of double sexual standard has been explored by a number of authors (Berrocal, 2019; Diéguez et al., 2003; Marks et al., 2019; Muehlenhard & Quackenbush, 1988; Pereira et al., 2008; Sakaluk & Milhausen, 2012; Seabrook et al., 2017; Sierra et al., 2007). With regard to the second line of investigation, significant links have, for example, been found between the SDS and gender (a greater level of SDS amongst men) (Diéguez et al., 2003), although several studies report that certain women do display more restricted standards towards themselves (González-Marugán et al., 2012; Gutiérrez-Quintanilla et al., 2010). Studies into links with age have shown that younger people exhibit greater adherence to the SDS (González-Marugán et al., 2012; Ubillos et al., 2016). Another factor which has been the focus of inquiry is religious practice (Pereira et al., 2008). For instance, the influence of parents’ religiousness on risky sexual behaviour (early sexual initiation, multiple sexual partners, and inconsistent use of the condom) has been studied, and has revealed greater levels of SDS amongst boys than amongst girls (Landor et al., 2011). Research has also highlighted the importance of the SDS due to its negative impact on sexual and mental health (Emmerink, 2017; Yela, 2012) as well as its influence on risk sexual behaviour (Álvarez-Muelas et al., 2020). Studies have been conducted into the links between the SDS and the application of contraceptive methods, highlighting their link to a greater risk of transmitting diseases (Ahmad et al., 2020; Caron et al., 1993).

Currently, there is a worrying rise in aggressive sexual behaviour amongst the young. In Spain, various studies have focused attention on sexual violence in universities (Osuna-Rodríguez et al., 2020; Sipsma et al., 2000). For example, it has been shown that 33.2% of the woman university students covered in the study had been subject to some form of unwanted sexual activity, including attempted rape (Sipsma et al., 2000).

Some works have pointed to the existence of a link between the SDS and sexual violence (Forbes et al., 2004; Shen et al., 2012). Sexist attitudes as well as beliefs and myths which justify rape have been associated with sexual coercion and aggression (Forbes et al., 2004). It has been pointed out that the presence of chauvinist attitudes is a risk factor for the existence of man’s violent behaviour towards women, and that the existence of such attitudes in women makes them potential abuse victims (Echeburúa & Fernández-Montalvo, 1998; Heise, 1998; Pulerwitz & Barker, 2008; Sierra et al., 2009). The SDS seems to play a key role in victimisation through the bullying of girls in secondary schools, since it encourages woman submission (Dunn et al., 2014). In addition, it is related to subjective sexual arousal (Sierra et al., 2019).

With regard to the third line of research, it should be mentioned that the most commonly used scales in Spain are the Double Standards Scale (DSS) (Caron et al., 1993); the Rape Support Attitude Scale (RSAS) (Lottes, 1991), applied to evaluate chauvinist attitudes amongst university students (Sierra et al., 2007), and the Scale for the Assessment of Sexual Standards Amongst Youth (SASSY) (Emmerink et al., 2017), which includes more recent aspects of double standards, and the Sexual Double Standards Scale (SDSS) (Muehlenhard & Quackenbush, 1988), which has led to detailed and interesting studies, among others those by (Gómez-Berrocal et al., 2019, 2019; Sánchez-Fuentes et al., 2020).

If, as mentioned, the SDS is related to aggressive sexual behaviour, specially among the youth, it seems important to ascertain its persistence as a first step towards designing psychological and educational work which must be carried out with the young in order to protect them against said violence.

The objectives of this work are to investigate, by means of the application of the SDSS, whether in the period 2015–2019 the SDS exists amongst the Spanish university population, and if men and woman obtain similar scores in the scale. We also explore the influence of factors such as gender and age on the SDS. The results are compared to previous researchs, conducted in different countries, in which the SDSS was also applied to university students (Diéguez et al., 2003; Muehlenhard & Quackenbush, 1988; Pereira et al., 2008; Sakaluk & Milhausen, 2012). In addition, students' responses to the items included in the scale are analyzed to attain a better understanding of relevant aspects of the different behaviour of men and women with regards to the SDS. Finally, through samples from 2018 to 2019, we examine whether issues related to the SDS create any kind of problem for students in their daily lives and in their interpersonal relations.

When starting this work, considering the social environment favourable to women (mobilizations, gender defense), we hypothesized (1) a decrease in the SDS with respect to the former available studies. In accordance with the above, and taking into account that the participants are also young people and university students, we also expected (2) that the SDS levels would be similar for men and women. Finally, since apparently the sexual behaviour of young people seemed to have evolved into more open forms, we expected as a new hypothesis (3) that SDS would not generate too many problems in their relationships and daily life.

Participants in the study were taking a degree in education, an aspect which we feel to be relevant since, as future teachers, they would have an enormous responsibility in the education of the young.

Materials and Methods

Participants

Five samples (one per year) of similar characteristics (age, place of studies, first year of the Bachelor’s Degree in Education at the University of Valladolid, Spain) were used. The total sample contained 531 students (165 men and 366 women), with an average age of 20.21 years (SD = 3.52). Recruitment was carried out from a non-random convenience sample. The size of the sample was determined by the number of students belonging to the selected courses, and who wanted to freely participate in the research. Additional details on the samples are given along tables.

Instruments

In Order to Evaluate the Moral Consideration of Sexual Behaviour Depending on Whether a Man or a Woman Who Performs It

The Sexual Double Standard Scale (SDSS) developed by Muehlenhard and Quackenbush (1988), (see Appendix A) was applied in its Spanish adaptation by Diéguez et al., (2003). The scale contains 26 items (individual and compared) and has a Likert-type response range with values between 1 (strongly agree) and 4 (strongly disagree). The global score of a given participant is calculated according to the expression included in Appendix A, and can vary from − 30 to + 48. A score equal to 0 indicates identical standards for both genders. Positive scores reveal more restricted standards towards women, while negative scores indicate more restricted standards towards men. The authors of the SDSS indicate that, in the case of the American sample, the test can be completed in just a few minutes. However, our participants, as was reported in other studies (Ubillos et al., 2016), spent an average of 20–30 min. The internal consistency of the SDSS for our total sample is acceptable. Cronbach’s α is equal to 0.69, similar to the value reported by Sakaluk and Milhausen (2012), α = 0.70.

To Study the Covariation of the SDS Due to Age

The participants’ age was classified into four levels: (a) 18–20, (b) 21–25, (c) 26–30 and (d) 31–50 years.

In Order to Study Whether the Concepts Related to the SDS Create Problems in Participants' Daily Lives

We asked students belonging to the samples of 2018 and 2019: have the topics dealt with in the SDSS created or do they create problems in your personal life? Likert-type responses are ranged between 0 (no problem) and 4 (many problems). Next, the participants were asked to write information on the back of the test: (a) about whether completing the questionnaire had difficulties for them; and (b) about any ideas they wanted to contribute on the subject studied.

Procedure

This is a cross-sectional survey-type descriptive study. It was repeated over five years (2015–2019). The tests were given out in the classroom, in the same contexts and conditions, by one of the researchers. The survey was completely anonymous and it was carefully explained to the students that the information gathered would be used solely for research purposes. Students were at all times completely free to participate in the investigation, and did not receive any type of reward or penalty for participating. The research respects the conventions and norms established in Spanish legislation for research involving people, as well as the protection of personal data. The study received approval from the Ethics and Research with Medicine Committee (CEIm) of the city of Valladolid’s East Health Area (University Clinic Hospital, University of Valladolid) under number PI 20–1680.

Data were analysed by means of the statistical program SPSS v25/Windows, considering a 95% confidence interval, an α error of 5% and a level of statistical significance p ≤ 0.05. Non-parametric tests were used if the distributions did not conform to normality and/or did not meet homoscedasticity criteria. Contingency tables, together with Pearson's \(\chi^{2}\), were applied to investigate differences between percentages. The significance of differences between mean scores obtained from the SDSS was analysed using the univariate GLM with the post hoc of multiple comparisons of Scheffé and Bonferroni contrasts. The results of differences between men and women from various studies were compared based on the descriptive and t value provided by each of the studies. The size of the effect for different groups was computed using the g of Hedges, which derives from the d of Cohen using a correction of a positive bias in the pooled standard deviation to avoid overestimation of the difference between means in the case of small samples. The following intervals for g are commonly considered: 0.1–0.3: small effect; 0.3–0.5: intermediate effect; 0.5 and higher: large effect. Finally, the existence of linear relationships between two variables, such as age and SDSS scores, was analysed using the Pearson’s correlation.

Results

The mean scores on the SDS for each year considered are listed in Table 1. Significant differences (p < 0.001) are specifically found between 2015 (6.10) and 2018 (3.95) as well as between 2015 and 2019 (4.54), i.e., there is a decrease in the SDS levels in 2018 and 2019, since the results become closer to 0.

Table 1 Comparison of means from the SDSS according to the year
Full size table

In order to analyse the gender as a possible differentiating factor, the global direct scores obtained from the SDSS application are presented first, and then by years. Later, the average scores are provided in order to facilitate statistical comparisons between them.

Direct scores obtained by women throughout the (2015–2019) period range between − 6 and + 16, while for men these values are − 1 and + 37 (Fig. 1). Taking a fairly restrictive value within the scale (e.g., + 9) regarding the women’s behaviour as a screening value, we note that 30.3% of men and 11.7% of women obtain equal or higher scores. The latter result reveals that, at least in several questions on the scale, women show more restrictive attitudes towards their own gender.

Fig. 1
figure 1

Frequencies (%) of mean scores obtained from the SDSS application according to the year and gender

Full size image

We find a gradual decrease from 2015 to 2019 in the scores, particularly in the most extreme ones (Fig. 1, Table S1). Thus, in 2015, very restrictive values were obtained against women's sexual behaviours since the maximum scores show very high values: + 37 (men) and + 16 (women). In 2016, maximum scores were + 19 for men and + 14 for women, and in 2017, + 14 and + 13, respectively. However, in 2018, the maximum man score decreased significantly. In fact, the maximum score for men was + 9, while for women it was + 12. In 2019, the maximum value from men again increased (+ 14), and was + 10 for women. As regards the mentioned screening value, in 2015, 49.1% of men and 24.0% of women obtained scores \(\ge\) + 9, while in 2018 the percentages decreased to 2.9 and 5.7%, respectively.

The average score obtained when applying the SDSS to the whole sample (i.e., including all the years), was 6.95 (SD = 5.04) for men, which is significantly higher (p < 0.001) than that obtained by women, 4.51 (SD = 3.22). In order to analyse whether this significant difference holds over time, a univariate model with a Bonferroni contrast was applied. The average scores obtained by men are much higher and statistically significant compared to those of women only in the first three years (p = 0.001 in 2015, p = 0.018 for 2016 and p = 0.006 for 2017, see Table 2 and Fig. 2). It should be noted that in 2018 and 2019 the mean scores in double sexual standard decreased, especially for men, with no significant differences between genders.

Table 2 Comparison of means from the SDSS according to the year and gender
Full size table
Fig. 2
figure 2

Comparison of means from the SDSS application according to the year and gender (error bars stand for the standard error of the means)

Full size image

Table 3 summarizes results for some items of the scale (see also the full Table S2). It lists the global percentage of men and women who select each of the response options to the scale items, as well as the average value obtained in each item (values ranged between 1 and 4). It is also analyses whether differences between genders are significant. We note that significant results are obtained for some of the comparisons (e.g., items 1, 2, 10 or 24). We now highlight some of the interesting results from the students’ responses. Women show more egalitarian attitudes towards both genders, yet also display greater reservations about sexual behaviours. Items 6 and 10 illustrate this statement. Women do not show any admiration for promiscuous or abundant sexual behaviour, scoring them with a high degree of disapproval, although similarly for both sexes. In contrast, men show high disapproval regarding women promiscuity, but point to a medium level of agreement regarding man behaviour. In the compared items 23 and 20, almost 50% of the woman sample expressed a high degree of disagreement regarding the need for sexual experience prior to marriage, while men attached greater importance to premarital experience. Items 2 and 24 are also very descriptive. Women express disagreement about early sexual experiences for both genders, which leads to a greater restriction against sexual behaviour in general (Eisenman & Dantzker, 2010). However, men indicate greater disagreement about early sexual experiences for woman adolescents compared to what they show for men.

Table 3 Comparison of percentages for some SDSS items according to gender
Full size table

Next, it is examined whether the SDSS scores of the whole sample vary with age. The results reveal a non-significant trend between both variables (Pearson’s correlation = 0.380; bilateral sig. = 0.098). If we study the difference in means taking into account simultaneously the variables age and gender, the Bonferroni post hoc confirms the existence of differences (p < 0.001) between the younger age ranges (González-Marugán et al., 2012; Legido-Marín & Sierra, 2010; Ubillos et al., 2016). Men between the ages of 18 and 20 and between 21 and 25 obtain much higher scores in the SDSS, that is, their SDS towards women is more restricted than that of women of the same ages (Table 4).

Table 4 Comparison of means from SDSS according to age groups and gender
Full size table

From the analysis shown in Table 5, which compares our results with those obtained in previous studies, it is observed that there are significant differences in the SDS between genders in all of them, except those carried out in the last two years of our research. In the mentioned studies, men obtain more restrictive scores towards the sexual behaviour of women. The values of the Hegdes’ g indicate that the greatest strength of the differences between genders occurs in the research conducted in Canada, being the size of the effect very important in the sample of our study of 2015, where a large g value is also obtained (Fig. 3).

Table 5 Comparison of mean scores from SDSS for different years and countries
Full size table
Fig. 3
figure 3

Comparison of mean scores obtained from SDSS applications: 2015–2019 (Global); 2018; 2019 (this work) and 2003 (Diéguez et al., 2003), (error bars stand for the standard error of the means)

Full size image

In order to work with students on this subject in the future, we examined not only whether double heterosexual standards persist, but also to what extent the concepts contained in the scale could cause problems in the students' personal lives. Table 6 and Fig. 4 show the differences by gender as well as the comparison between these data with the average score obtained when applying the SDSS. Data reveal that problems are more relevant for women, since 56.0% of women and 80.4% of men show no concern regarding this matter (levels 0 and 1). At level 2, women almost triple the percentage of men (28.4% vs. 10.9%). When the percentage of the two most problematic levels is observed (3 and 4), the percentage of women with problems with regards to double sexual standard is still higher; 15.5% of the sample versus 8.6% of men. Pearson's χ2 between the frequencies (%) obtained by each gender is significant. From the comparison with the SDSS scores, it seems that there is an increase in the most restrictive values when problems increase. This occurs in the women case at levels 2 and 3, such that their average score is higher. It is worth noting that the small number of participants, both woman and man, who mark level 4 have the least restrictive and most egalitarian score with regard to sexual standards.

Table 6 Pearson’s \(\chi^{2}\) in the study of level of problems
Full size table
Fig. 4
figure 4

Frequencies (%) of level of problems (0- none, 4-many) created by SDS issues analyzed in the SDSS

Full size image

We now provide a summary of the qualitative information obtained from the comments given freely by the students. It should be noted that they remark that the different treatment of the sexual behaviour of men and women is a non-solved issue in society, uncomfortable to deal with and about which it is not easy for them to talk. For this reason, most of the participants who have responded agree on the need for educational treatment. Taking into account that many of their comments are matching, we have considered pertinent to group them according to the different most cited topics. These refer, among others, to the deficiencies found in the test and to the difficulties they had to complete it; the finding that society has not assumed that men and women should be judged in the same way for the same sexual behaviour, with few social changes at this regards. For the sake of clarity, Table 7 shows the mentioned classification, including examples of the behaviours that students cite most insistently.

Table 7 Summary of the responses freely given by the participants
Full size table

Discussion

Contrary to our first two hypotheses, one of the main results from this study is that the SDS continues to persist in university students, especially in men, although the differences between genders are equalizing. In the last two years, particularly in 2018, men's scores start to be less restrictive towards women, and extreme scores drop significantly. That is, the sexual behaviour of men and women begins to be judged in a more equal way, although differences still remain. This is consistent with the fact that the social concept of SDS is not easy to eliminate (Amaro et al., 2020).

In addition, it is necessary to take into account the information provided by the students on how they live this issue. In this sense, our third hypothesis has not been corroborated. It seems that there is still an important problem that affects to both their interpersonal relationships and their daily life, especially in women. It should be noted that up to the 15.5% of them claims to have significant problems.

Regarding the present situation and the possible improvements that could be made, the participants provided valuable ideas. The question put to them and the comments that they freely wrote remarked the importance that the said question had for the students to reflect on their attitudes towards SDS and to understand those that are prevalent in their immediate environment and in society as a whole. Only when they were required to take a position with regards to the SDS, the students reacted and were really aware of their ideas. Thus, in the qualitative information, they stated that the issues involved in the test are current in society, that there are still taboos, absence of normality when these issues are treated and lack of respect with regard to the sexual behaviour of others, an attitude difficult to change and that it has been indicated previously (Amaro et al., 2020; Marks & Fraley, 2005; Soller & Haynie, 2017; Zaikman et al., 2016). Another key factor, also suggested by students, involves updating study methods. Most research into the SDS is based on quantitative techniques (scales, questionnaires), that have not incorporated other behaviours, such as mixed relationships or groups with different sexual trends (LGTBI). Participants also indicate that some questions should be re-formulated since a number of students had problems and did not know which answer to select for some of the test items.

Once the test evaluation process was completed, we noted that the participants had the need to comment and express their opinions. They showed how difficult it was to deal with these issues. For example, they stated that such issues are not dealt with normally, and they even highlighted how the simple act of completing the test generated real concern in some of them. Riemer et al. (2014) investigated on how women perceive potentially sexist attitudes by men. This work has to continue, but it has to be carried out with both sexes, since, as our study shows, both women (González-Marugán et al., 2012; Gutiérrez-Quintanilla et al., 2010) and men may have restrictive ideas regarding the sexual activity by women. Instilling equalitarian sexual moral that embraces freedom of personal action is by no means an easy task. It forms part of a personal and social process which merges individual work and group reflection in educational settings. Work must be carried out with the cognitive, affective and behavioural components. A shift in attitudes towards the SDS will require more time and effort than is devoted to the change in the understanding of the sexual activity and of related problems, an aspect on which more work has been done in sexual education programmes in high schools. Students agree on the need for sexual and affective education from elementary school to achieve a normalization of the issue. Training with group dynamics techniques can provide information about the opinions and attitudes of others on the subject, and can increase the own understanding on the mentioned subject, as well as self-knowledge. This could be useful so that students can defend their right to personal freedom (Santos-Iglesias & Sierra, 2010) always respecting the different ways of understanding the sexuality of others (basic assertive rights of the person).

Limitations and Future Work

The present research is based on a descriptive methodology that should be completed with an experimental treatment. Design trainings (involving both control and experimental groups) that address these issues, especially in secondary school as a preventive measure, would be convenient. It is also interesting to use the assessment instruments in the student training processes, which, obviously, also implies an adequate training of teachers and professors. The evaluation of the SDS should be extended to samples of different ages and populations. Updated evaluations and scales are also necessary. In this context, we are applying a new instrument that facilitates reflection on sexual stereotypes (some questions included are: do women or men have to renounce what they are to become equal to the other sex?; are women more affective in sexual activity?; is the difference between men and women a social issue?…). At present, we are constructing a questionnaire that relates these concepts to couple relationships, pornography, sexual identity, harassment and victimization, etc. The complex relation between variables such as permissibility, victimisation, aggression, assertiveness, fear, isolation and socialisation with the SDS, partially pointed out in the work by Vrangalova and Bukberg (2015), should be explored more deeply.

Conclusions

This study, together with the previous ones considered, shows that, despite society's more open view on sexual behaviour, the SDS is still more restrictive towards women, particularly on the part of men. Despite this, more egalitarian attitudes have been achieved in the last two years. Especially the most extreme scores from the SDSS have been removed. Some men admire behaviours in them, such as promiscuity, premarital experiences, or early experiences, which are more indifferent to women. Women claim to have more problems related to this issue in their daily life, especially with regards to the judgments made about their sexual activity. In addition, they highlight the existence of few changes since men and women are still judged differently for the same actions (for example, having a high number of sexual partners). The data provided by the students reveal the existence of taboos and the lack of normality when talking about sexuality. It is remarked the need to improve the evaluation instruments that must include, e.g., new groups with different sexual tendencies (LGTBI) or open relationships. As a preventive measure, education from primary school is required to promote equality and avoid social stereotypes, as well as to develop the assertive freedom of each person regardless of their gender.